You should enter zero if all your wages were earned in Detroit.
In order to claim fewer days worked in Detroit, a work log would be required as well as a letter from the employer.
According to the City of Detroit:
“NONRESIDENTS AND PART-YEAR RESIDENTS ONLY PART 3: WAGE ALLOCATION FOR NONRESIDENTS AND PART-YEAR RESIDENTS Part 3 is used by nonresidents and part-year residents to compute wages earned in Detroit. Do not complete Part 3 if all of your work is performed in Detroit because all wages are subject to tax…”
**Say "Thanks" by clicking the thumb icon in a post
**Mark the post that answers your question by clicking on "Mark as Best Answer"